recurrent nova

"Frequent monitoring is requested of the recurrent nova U Scorpii over the next year or so to discover the upcoming very-fast eruption. The predicted outburst is for the year 2020.0±0.7. The eruption is likely within the next year, but it could well go off tonight.

The HST COS observations have been scheduled to take place during the window of 2018 October 4 - 6. It is essential to know the status of T Pyx in order for the HST team to safeguard the instrumentation and make a final decision about approving the COS observations.

October 31, 2017: Further to AAVSO Alert Notice 603, your positive observations of CI Aql, which will be used to determine whether the HST observation of CI Aql will take place, must be submitted to the AAVSO International Database by 14:45 UT (10:45 am EDT) on Wednesday, 2017 November 1. Without these positive ground-based observations reported by this time (and showing CI Aql not in outburst), the HST observation will not take place.

October 27, 2017 : Further to AAVSO Alert Notice 599, Dr. Edward Sion (Villanova University) informs us that the HST COS observation of the recurrent nova CI Aql has been scheduled for November 2, 2017.

October 1, 2017 : Dr. Edward Sion (Villanova University) has requested AAVSO observers' assistance in monitoring the recurrent nova CI Aql in support of observations with the Hubble Space Telescope Cosmic Origins Spectrograph scheduled for October 30 - November 6, 2017. These observations are part of a study on short orbital period recurrent novae as Supernovae Type Ia progenitors.

October 19, 2016: Dr. Edward Sion (Villanova University) has requested AAVSO observers' assistance in monitoring the recurrent nova CI Aql in support of observations with the Hubble Space Telescope Cosmic Origins Spectrograph scheduled for October 31 - November 2, 2016, and November 3 - November 5, 2016. These observations are part of a study on short orbital period recurrent novae as Supernovae Type Ia progenitors.